This invention relates to a chocolate feeding and control system for chocolate refiners.
As is known in the art, chocolate refiners have the function of "rolling" the chocolate paste being fed in in order to impart to it a desired fineness. This is selected according to the intended final use of the chocolate in a variety of different products. Measuring the fineness of the chocolate film being delivered by the refiners presents considerable difficulties and is generally carried out in an empirical fashion.
Italian Patent Application No. 20 718 A/83 (U.S. Pat. No. 4,519,304) by this Applicant discloses a device for adjusting and monitoring the thickness of the film being delivered by refiners, which enables the achievement of fineness grades which are required and preset. With that device, it is possible to directly adjust a refiner so as to maintain set fineness values.
With conventional refiners, not only is fineness control achieved through an empirical and unreliable procedure, but no provision is made for controlling the effective production rate of the machine. With prior refiners, moreover, the chocolate paste is fed from the conveyor by means of a removal blade operated with a knife-like action and set for oscillation in a vertical plane, and the chocolate is introduced into the hopper at its middle. This creates peak or heaped areas at the middle, and accordingly, different depths which lead to irregular filling, which is reflected in the filling chamber which is provided with the feed roll pair.
Furthermore, with prior refining machines, the feed chamber includes a capacitive sensor for sensing the minimum and maximum levels of the chocolate. These sensors operate erratically owing to the formation of incrustations. This results in untimely filling of the chamber, so that, in the event of the minimum levels being too low, hollows or pockets are formed close to the second roll in the feed roll pair, which pockets may create objectionable "dry zones or bands" or uneven thickness in the chocolate film being formed.